Influence of two ddifferent nnozzle fforms on the flow ffield and heat transferring characteristics of qquick freezer

Authors

WANG Jinfeng, College of Food Sciences &Technology, Shanghai Ocean University, Shanghai 201306, China; Quality Supervision, Inspection and Testing Center for Cold Storage and Refrigeration Equipment, Ministry of Agriculture, Shanghai 201306, China; Shanghai Professiona
LI Wenjun, College of Food Sciences &Technology, Shanghai Ocean University, Shanghai 201306, China; Quality Supervision, Inspection and Testing Center for Cold Storage and Refrigeration Equipment, Ministry of Agriculture, Shanghai 201306, China
XIE Jing, College of Food Sciences &Technology, Shanghai Ocean University, Shanghai 201306, China; Quality Supervision, Inspection and Testing Center for Cold Storage and Refrigeration Equipment, Ministry of Agriculture, Shanghai 201306, China; Shanghai Professiona
YANG Dazhang, College of Food Sciences &Technology, Shanghai Ocean University, Shanghai 201306, China; Quality Supervision, Inspection and Testing Center for Cold Storage and Refrigeration Equipment, Ministry of Agriculture, Shanghai 201306, China; Shanghai Professiona
LIU Yuyan, College of Food Sciences &Technology, Shanghai Ocean University, Shanghai 201306, China; Quality Supervision, Inspection and Testing Center for Cold Storage and Refrigeration Equipment, Ministry of Agriculture, Shanghai 201306, China
LU Weihua, Nantong Square Cold Chain Equipment Company, Nantong, Jiangsu 226371, China)
YANG Xiaoyan, Nantong Square Cold Chain Equipment Company, Nantong, Jiangsu 226371, China)

Abstract

In this study, V type slit nozzle and straight seam hole plate in a quick freezer was used to invetigatethe effect by the change of distance (H) between the nozzle and the plate surface on the internal flow field and the pressure field in a freezer with these two kinds of nozzle structures under the same air condition. Moreover, the metal surface heat transfer characteristics were also studied. The results showed that the flow resistance of the straight slot seam orifice was smaller than that of the V type slot nozzle along the cross-flow direction. The pressure range along cross flow direction of the V slot nozzle was significantly less than that of the flat nozzle, when the jet-to-plate spacing Hs（Hs=H/s）was at the small value, and the V slot nozzle outlet velocity uniformity was higher than that of straight slotted orifice. The velocity along cross-flow direction in flat nozzle was higher than that of the V slot nozzle, which was not good to safe and effective production for an air impact freezer. Compared with the flat nozzle quick freezer, the difference of the Nu number on the surface of the steel strip of the V slot nozzle was obviously smaller, and the average Nu number of the V slot nozzle was greater than that of the flat nozzle. The overall flow and heat transfer characteristics of the V slot nozzle was better than those of flat nozzle, and the heat transfer uniformity of metal surface of the V slot nozzle was also better than that of flat nozzle.

Publication Date

12-28-2017

First Page

80

Last Page

85,90

DOI

10.13652/j.issn.1003-5788.2017.12.016

Recommended Citation

Jinfeng, WANG; Wenjun, LI; Jing, XIE; Dazhang, YANG; Yuyan, LIU; Weihua, LU; and Xiaoyan, YANG (2017) "Influence of two ddifferent nnozzle fforms on the flow ffield and heat transferring characteristics of qquick freezer," Food and Machinery: Vol. 33: Iss. 12, Article 16.
DOI: 10.13652/j.issn.1003-5788.2017.12.016
Available at: https://www.ifoodmm.cn/journal/vol33/iss12/16

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